A modified transforaminal lumbar interbody fusion technique to decrease the incidence of postoperative radiculopathy: A prospective analysis of 216 patients

Abstract

Reported incidence of postoperative intractable radiculopathy following posterior lumbar interbody fusion (PLIF) and transforaminal lumbr interbody fusion (TLIF) is between 7-14% affecting postoperative recovery. Excessive medial dural retraction in PLIF and exiting nerve root injury in TLIF during cage insertion are the proposed itiologies for battered root syndrome. Aim of the study was to identify the incidence of postoperative radiculopathy on the side of cage insertion following a modified TLIF technique. 216 patients who underwent fusion by modified-TLIF approach were prospectively analyzed. The inferior facet of cranial vertebra alone was excised retaining the pars interarticularis of cranial vertebra and superior facet of caudal vertebra which from the posterior wall of intervertebral foramen. It provided adequate space for cage insertion without need for excessive dural retraction in addition to protecting the exiting nerve root. The severity of postoperative radiculopathy on the side of cage insertion was assessed by visual analog scale (VAS). Of the 216 patients, L4-5 level was fused in 137, L5-S1 in 72 and L3-4 in 7 patients. Severe postoperative radiculopathy (VAS: 10) was observed only in three patients with an incidence of 1.4% who needed prolonged hospitalization for its recovery. L3-L4 was the fused level in these three patients while none of them in L4-5 and L5-S1 levels had such severe radiculopathy. Lumbar interbody fusion by modified TLIF (Hemi-TLIF) approach involving excision of only the inferior facet decreases the incidence of post-operative radiculopathy. However, we recommed this procedure only at L4-5 and L5-S1 levels where the spinal canal is relatively larger when compared to higher lumbar levels.